Please Don't Use the Word 'Brittle' With Diabetes

Miriam E. Tucker


April 12, 2021

Soon after I was diagnosed with type 1 diabetes (in 1973), I was told that the term "brittle" shouldn't be used in the context of diabetes because it was outdated and inappropriate. Its use seemed to diminish for a while, but to my dismay, it's back.

I see people in type 1 diabetes Facebook groups describe themselves as "brittle diabetics" at least weekly. Many say that they were diagnosed as such by their doctors, both primary care and endocrinologists. In fact, "brittle diabetes" is now all over the internet, even on official sites, including those of the US Food and Drug Administration and the National Institutes of Health. In the first case, they are actually referring to hypoglycemic unawareness; in the second, it's listed under "genetic and rare diseases," though it's neither.

I am not a clinician, but I am both a person living with type 1 diabetes and a journalist who has covered the complex and nuanced science around diabetes for over 30 years, primarily for healthcare professional audiences. In my view, the term "brittle" is unscientific, unhelpful, and potentially harmful.

What Is Meant by 'Brittle Diabetes'?

"Brittle diabetes" has been defined many ways, but it essentially means that the person has very labile blood sugar levels, usually in the context of type 1 diabetes. Yet, glycemic lability is a hallmark of type 1 diabetes, an autoimmune condition in which there is an absolute absence of endogenous insulin production. Blood sugar fluctuations are typically far less dramatic with type 2 diabetes, characterized by relative insulin deficiency in the presence of insulin resistance.

With type 1, it's incredibly challenging to keep blood sugars in tight optimal range, even with today's insulin pump and continuous glucose monitoring technology — and many patients still don't have access to those. Some people have more difficulty than others in keeping blood glucose levels in optimal range, but that doesn't mean that they have a different type of diabetes.

There are specific, discoverable reasons for blood sugar fluctuations. And even if the reasons can't always be discerned, they still exist. There is no special type of diabetes due to evil supernatural forces, much as it may seem that way at times. Yet, that's how the term is often used by healthcare professionals and perceived by patients.

How the Label Causes Harm

Of concern, use of the label "brittle diabetes" can discourage investigation for underlying causes of extreme glucose variability, such as hypoglycemic unawareness, gastropathy/gastroparesis, cognitive problems, mental health issues such as depression and eating disorders, insulin resistance, and/or insulin rationing because of cost. Each of these conditions has its own name and appropriate course of action; there's no need for an additional unhelpful wastebasket term.

I'm also concerned that the term might be applied to people with unrecognized adult-onset type 1 diabetes. Only recently has evidence revealed that type 1 (autoimmune) diabetes — previously called "juvenile diabetes" — can not only present at any stage of adulthood, but is also nearly as likely to arise after age 30 years as before.

Misdiagnosis of adult-onset type 1 as type 2 diabetes is a known phenomenon and can result in delayed and/or insufficient initiation of insulin treatment, as well as denial of insurance coverage for diabetes technology.

When people on Facebook describe themselves as "brittle diabetics" without specifically saying that they have type 1, I always wonder whether they've received a correct diagnosis.

Alternative Labels Don't Work Either

Some have proposed using terms such as "labile," "unstable," or "uncontrolled" diabetes, but those share some of the same problems as we see with "brittle."

The diabetes per se isn't "labile" or "unstable," the blood sugars are. The terms "uncontrolled" or "poorly controlled" add an element of judgment, implying that the patient is to blame. They also fail to acknowledge achievement of target blood glucose levels at particular points in time. Those moments of triumph, even if fleeting, can mean a lot to patients who are struggling to manage type 1 diabetes.

That said, I would argue that the word "brittle" is particularly egregious. When applied to bones, it means that they're inflexible and easily broken. I hope that no clinician sees me — or wants me to see myself — that way.

Speaking From Experience

I completely understand the infuriating unpredictability of swinging blood sugar levels in type 1 diabetes because I've been living with them for 47 years. I currently wear an insulin pump and a continuous glucose monitor, which aren't yet integrated to semi-automated insulin delivery as are some systems currently on the market. I expect to be using one of those systems soon.

Though I usually know the reasons for my lows and highs, I'm often surprised by their extent and variation from day to day. Sometimes highs come out of nowhere. I'll go through the checklist: bad pump site (occasionally), bad insulin (rarely), or carb underestimation (often). If it's none of those, I'll ascribe it to stress, shrug, and give myself insulin to correct it. I do not call myself or my diabetes "brittle." It's just type 1 diabetes doing its mean thing.

What Can Be Done?

Ongoing improvements in closed-loop automated insulin delivery are proving to minimize glycemic variability. Two such hybrid systems currently on the US market are the Medtronic MiniMed 670G Hybrid Closed-Loop System and the Tandem t:slim X2 insulin pump with Control-IQ technology. More are on the way.

In the meantime, even stand-alone continuous glucose monitors can make a huge difference in allowing wearers to see their blood glucose levels in real time and react to correct and prevent highs and lows.

Access to diabetes technology is a problem, though, and not just due to financial reasons. Recent studies have shown that Black children and young adults with type 1 diabetes are significantly less likely to be prescribed insulin pumps, even when insurance coverage isn't an issue.

Other measures that some patients find helpful for reducing post-meal glucose spikes include low-carb diets and the very rapid-acting inhaled insulin Afrezza.

Two helpful books for patients are Think Like a Pancreas, by Gary Scheiner, CDCES, for those with either type of diabetes who use insulin, and Sugar Surfing, by Stephen W. Ponder, MD, for those with type 1 diabetes. Both authors are esteemed professionals who live with type 1 diabetes themselves.

I look forward to your comments.

Miriam E. Tucker is a regular Medscape contributor who has lived with type 1 diabetes since 1973. She can be found on Twitter @MiriamETucker.


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